Integrated balun and coupler transformer

Abstract

Integrated balun and coupler is described. In one example, a radio frequency (RF) device includes a balun and coupler. The balun includes a first winding and a second winding arranged on a magnetic core. Respective inputs of the first winding and the second winding are configured to receive a balanced RF input and respective outputs of the first winding and the second winding are configured to provide a first unbalanced RF output. The coupler includes a third winding arranged on the magnetic core. The third winding is configured to provide a second unbalanced RF output, where the second unbalanced RF output is a fraction of the first unbalanced RF output.

1. A radio frequency (RF) device, comprising:
 a balun having a first winding and a second winding arranged on a magnetic core, respective inputs of the first winding and the second winding configured to receive a balanced RF input, and respective outputs of the first winding and the second winding configured to provide a first unbalanced RF output; and 
 a coupler having a third winding arranged on the magnetic core, the third winding configured to provide a second unbalanced RF output, said second unbalanced RF output being a fraction of the first unbalanced RF output, 
 wherein a number of turns of the first winding is equal to a number of turns for the second winding, and a number of turns of the third winding is less than the number of turns for the first winding and the second winding. 
 
     
     
       2. The device of  claim 1 , wherein the magnetic core comprises a ferrite core. 
     
     
       3. The device of  claim 1 , wherein the third winding includes at least a single turn. 
     
     
       4. A radio frequency (RF) device, comprising:
 a balun having a first winding and a second winding arranged on a magnetic core, respective inputs of the first winding and the second winding configured to receive a balanced RF input, and respective outputs of the first winding and the second winding configured to provide a first unbalanced RF output; and 
 a coupler having a third winding arranged on the magnetic core, the third winding configured to provide a second unbalanced RF output, said second unbalanced RF output being a fraction of the first unbalanced RF output, 
 wherein the magnetic core comprises a body having a first end, a second end, a first bore, and a second bore, each of the first bore and the second bore traversing a length of the body between the first end and the second end, the first bore and the second bore positioned to define a central vane. 
 
     
     
       5. The device of  claim 4 , wherein each of the first winding, the second winding, and the third winding comprise a conductive wire wrapped around the central vane through the first bore and the second bore. 
     
     
       6. A radio frequency (RF) system, comprising:
 a balanced source for providing a balanced RF signal; 
 an unbalanced load for receiving an unbalanced RF signal; 
 a circuit for receiving a sample of the unbalanced RF signal; 
 an integrated balun and coupler having a first winding, a second winding, and a third winding arranged on a magnetic core, respective inputs of the first winding and the second winding configured to receive the balanced RF signal, respective outputs of the first winding and the second winding configured to provide the unbalanced RF signal, and the third winding configured to provide the sample of the unbalanced RF signal, 
 wherein a number of turns of the first winding is equal to a number of turns for the second winding, and a number of turns of the third winding is less than the number of turns for the first winding and the second winding. 
 
     
     
       7. The system of  claim 6 , wherein the magnetic core comprises a ferrite core. 
     
     
       8. The system of  claim 6 , wherein the third winding includes at least a single turn. 
     
     
       9. A radio frequency (RF) system, comprising:
 a balanced source for providing a balanced RF signal; 
 an unbalanced load for receiving an unbalanced RF signal; 
 a circuit for receiving a sample of the unbalanced RF signal; 
 an integrated balun and coupler having a first winding, a second winding, and a third winding arranged on a magnetic core, respective inputs of the first winding and the second winding configured to receive the balanced RF signal, respective outputs of the first winding and the second winding configured to provide the unbalanced RF signal, and the third winding configured to provide the sample of the unbalanced RF signal, 
 wherein the magnetic core comprises a body having a first end, a second end, a first bore, and a second bore, each of the first bore and the second bore traversing a length of the body between the first end and the second end, the first bore and the second bore positioned to define a central vane. 
 
     
     
       10. The system of  claim 9 , wherein each of the first winding, the second winding, and the third winding comprise a conductive wire wrapped around the central vane through the first bore and the second bore. 
     
     
       11. A radio frequency (RF) device, comprising:
 a balanced RF port having a positive terminal and a negative terminal; 
 a first unbalanced RF port having a positive terminal and a ground terminal; 
 a second unbalanced RF port having a positive terminal and a ground terminal; 
 a magnetic core; 
 a first winding arranged on the magnetic core and coupled between the positive terminal of the balanced RF port and the positive terminal of the first unbalanced RF port; 
 a second winding arranged on the magnetic core and coupled between the negative terminal of the balanced RF port and the ground terminal of the first unbalanced RF port; and 
 a third winding arranged on the magnetic core and coupled between the positive terminal and the ground terminal of the second unbalanced RF port; 
 wherein a number of turns of the first winding equals a number of turns of the second winding, and a number of turns of the third winding is less than the number of turns for the first winding and the second winding. 
 
     
     
       12. The device of  claim 11 , wherein the magnetic core comprises a ferrite core. 
     
     
       13. The device of  claim 11 , wherein the third winding includes at least a single turn. 
     
     
       14. The device of  claim 11 , wherein the magnetic core comprises a body having a first end, a second end, a first bore, and a second bore, each of the first bore and the second bore traversing a length of the body between the first end and the second end, the first bore and the second bore positioned to define a central vane. 
     
     
       15. The device of  claim 14 , wherein each of the first winding, the second winding, and the third winding comprise a conductive wire wrapped around the central vane through the first bore and the second bore. 
     
     
       16. The device of  claim 11 , wherein the positive terminal of the balanced RF port and the positive terminal of the first unbalanced RF port comprise respective ends of the first winding, the negative terminal of the balanced RF port and the ground terminal of the first unbalanced RF port comprise respective ends of the second winding, and the positive terminal and the ground terminal of the second unbalanced RF port comprise respective ends of the third winding.